Gutted. Picked off the loose bits. Whole bumper re-spray?

Gutted for you. Such a PITA when that sort of thing happens. I've reversed into many things over the last 30yrs, we're only human!

 

I would have thought a decent smart repair guy should be able to sort that out. They can use heat to get it back to shape.

Bumper shape isn't distorted. Just paint and primer cracked badly so picked off.

I’d paint the entire bumper. But it depends on what you expect from it. I can’t deal with ghosting or colour issues, so I always do the entire panel. 

Being silver / grey paint match on that will be a nightmare, especially if you do the whole bumper as every surface will contrast with the adjoining panel. 

 

Because the paint loss is only on one plane / surface, a friendly dentless outfit will likely do a good job by filling and spraying only the top plane

I would fill it only paying attention to the feather out on the rearmost edge, I would use masking tape so that the repair does not go down to the vertical section.

 

Then I would fit a rubber, plastic or metal bumper protector as much to the rear as possible, that will leave only a tiny touch up to contend with, you could even run a bead of sikaflex along that edge to hide it completely.

 

I used the cheapest rubber one from Ali-Express, it came rolled up and when flattened the curve did not match my bumper but it was flexible enough to exactly follow the form when applied with care from the centre outwards using contact adhesive and a masking tape guide.

My good lady wife did exactly the same thing today, whilst 3-point turning.

The damage looks very much the same, being confined to the flat top surface.

 

I have a stick-on transparent, plastic film, scratch protector in that area and the damage is underneath that.

I think I will follow J.R's wise advice above and put a plastic or stainless steel protector plate over the damage and forget  about it.

 

Now...how to get the cost of the part out of her?